Crash of cursor.execute() when passing mapping as args in 1.4.0.

[felixxm]

In the Django's test suite we encounter issues with mysqliclient==1.4.0. cursor.execute() crashes when passing mapping in args, e.g.

cursor.execute(
    'SELECT * FROM raw_query_author WHERE first_name = %(first)s',
    {'first': 'Bob'},
)

Stacktrace:

MySQLdb/cursors.py", line 188, in execute
    query = query % args
KeyError: b'first'

It is probably related with 5e8eeac.

See test failure.

[felixxm]

Encoding keys fixed issue for me:

diff --git a/MySQLdb/cursors.py b/MySQLdb/cursors.py
index b8c0d88..e612f1a 100644
--- a/MySQLdb/cursors.py
+++ b/MySQLdb/cursors.py
@@ -181,7 +181,7 @@ class BaseCursor(object):
 
         if args is not None:
             if isinstance(args, dict):
-                args = dict((key, db.literal(item)) for key, item in args.items())
+                args = {key.encode(db.encoding): db.literal(item) for key, item in args.items()}
             else:
                 args = tuple(map(db.literal, args))
             try:

[methane]

(side note: why HISTORY.rst does not contain info about the drop of Python 3.4 support?

Just missed.

It also breaks semver)

I'm not follow semver strictly. Especially, many projects drop old Pyhton support without increasing major version. Django 2.1 dropped Python 3.4 support too.

[felixxm]

@methane Many thanks for the new release 🍾 🎉